the upper part of the lower peninsula of michigan. there were suddenly a large number of people in relatively small communities with very severe, bloody, diarrheal illness. and when these people went to their health care providers, the health care providers took specimens, tested them for the bugs that they knew caused that type of bloody diarrhea and came up with nothing. they turned first to the local, then to the state public health department, and when that didn't turn up any answers, the state asked the cdc for assistance. and so in circumstances where people can't come up with the causative agent, those specimens can then come into our laboratories, and we can run tests for a variety of different things that are both known and unknown. and that's what we did in that particular situation. and one of the things that we noticed is that we found that there were unusual e. coli in several of the specimens that were submitted to us from both oregon and from michigan. now, everyone normally has e. coli in their g.i. tract. it's a norma